D defs.my
Entry 1 sense Webster, 1913

Harum-scarum

/(hâr"ŭm*skâr"ŭm)/ · Har·um-scar·um · IPA /ˌhɛəɹəmˈskɛəɹəm/
01 a. Wild; giddy; flighty; rash; thoughtless.
  1. 1.
    Wild; giddy; flighty; rash; thoughtless.[Colloq.]
    “They had a quarrel with Sir Thomas Newcome's own son, a harum-scarum lad.” Thackeray.